The invention relates to copiers of the type comprised of a transparent support upon which originals to be copied are laid with their image-bearing sides face down, illuminating means for illuminating the image-bearing sides of such originals and means for forming reproductions of the illuminated originals. The transparent support is most often a planar or part-cylindrical glass plate.
It is already known to use a copier of the type in question to effect the reproduction of only selected portions of individual originals. It is for example known to use a selecting arrangement to charge only linear sections of a photoconductive printing form secured to a rotating printing element, with the charged linear sections corresponding to the portions of the original selected for reproduction. Alternatively, it is known to control the illumination of the image-bearing side of the original in a sectional manner to make possible the transfer of the printing form of only selected sections of the image.
The known expedients serve their purpose. However, they require special design of the copier proper. If an attempt is made to apply one of the known expedients to a copier of conventional design, the number of modifications which must be made in the copier proper is very considerable.